1. Technical Field
The present disclosure relates generally to medical catheter apparatus, and more particularly to a multiple lumen catheter having a catheter tip that prevents occlusion during use.
2. Description of the Related Art
Some known catheters are tubular, flexible medical devices for administration of fluids (withdrawal, introduction, etc.) within cavities, ducts, vessels, etc. of a body.
These catheter devices may be employed for administration of fluids that includes the simultaneous introduction and withdrawal of fluid for applications such as, surgery, treatment, diagnosis, etc. In one particular hemodialysis application, blood is withdrawn from a blood vessel for treatment by an artificial kidney device and the treated blood is introduced back into the blood vessel.
Various known catheter devices have been employed for simultaneous withdrawal and introduction of fluid with a body. These devices may utilize multiple lumens, such as dual lumen catheters that facilitate bi-directional fluid flow whereby one lumen performs withdrawal of blood and the other lumen introduces treated blood to the vessel. During an exemplary hemodialysis procedure, a multiple lumen catheter is inserted into a body and blood is withdrawn through an arterial lumen of the catheter. This blood is supplied to a hemodialysis unit which dialyzes, or cleans, the blood to remove waste and excess water. The dialyzed blood is returned to the patient through a venous lumen of the catheter. Typically, the venous lumen is separated from the arterial lumen by an inner catheter wall, called a septum.
In addition, catheters can have a third lumen used, for example, in hemodialysis treatment of patients that require infusion of medication, blood sampling and/or pressure measurement in a vessel to control the infusion rate of intravenous fluids. Such catheters including at least three lumens facilitate simultaneous hemodialysis and other forms of fluid administration as described.
The efficiency of a hemodialysis procedure may be reduced by undesirable recirculation of blood flow whereby the dialyzed blood exiting the venous lumen is directly returned to the arterial lumen. To overcome this drawback some catheter devices stagger the openings of the lumens such that the opening of the venous lumen is disposed distally beyond the opening of the arterial lumen.
These catheter devices, however, also suffer from various additional drawbacks. For example, blood clots can form adjacent to or on the opening of both lumens and at locations between the openings of the lumens. Another drawback that may arise, due to the dedicated flow direction for a particular lumen, is recirculation if the flow direction is reversed. Further, suction introduced through lumen openings of the prior art may draw portions of a body vessel wall therein. These drawbacks can disadvantageously result in flow occlusion.
Therefore, it would be desirable to overcome the disadvantages and drawbacks of the prior art with a multiple lumen catheter including a catheter tip that prevents occlusion during use to facilitate unobstructed fluid flow. It would be desirable if such a catheter included concave surfaces adjacent the catheter tip to prevent occlusion and undesirable recirculation. The catheter may also facilitate reversible flow between lumens of the catheter. It would be highly desirable if the catheter and its constituent parts are easily and efficiently manufactured and assembled.